Details disclosed in this section merely offers background information regarding embodiments of the present invention. No determination has been made, and no assertion is made, as to whether any of the below might be applicable as prior art with regard to the present invention.
Normally, a location based service (LBS) is a system and service for tracking, identifying and utilizing the location of a person or thing, based on a wired/wireless communication network. Namely, using positioning or location-estimating technique, the LBS determines in real time the location of a user (i.e., a subscriber) of a mobile communication device, such as a smart phone or a cellular phone, and offers the determined location to the user.
As to the LBS, a variety of techniques such as a global positioning system (GPS), Wi-Fi geotagging, triangulation using base stations, and the like are known in the art. Recently, Wi-Fi positioning system (WPS) technique based on wireless local area network (WLAN) is also known.
The WPS refers to technique to allow a user's terminal device to receive parameters (e.g., a media access control (MAC) address, signal strength, etc.) of radio frequency (RF) signals emitted from access point (AP) devices and also allow a WPS server to compute and determine the location of the terminal device (i.e., a user location) by using positioning technique.
A typical location-estimating technique using AP devices has, however, a problem of requiring a complicated mathematical computation. It is therefore difficult to apply this technique to a device with low performance. Even though being applied actually, this technique has a burden of much time to estimate a user location due to a complicated computation process.
Additionally, such a location-estimating technique using AP devices is often used for estimating a user's indoor location. However, when a user is in a multi-floor structure, it is not easy to exactly know what floor a user is located on.